Evaluate (9-4 square root of 5)^3+1÷((9-4 square root of 5)^3)

${(9 - 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Step 1

Simplify each term.

Use the Binomial Theorem.

$9^{3} + 3 \cdot 9^{2} (- 4 \sqrt{5}) + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Simplify each term.

Raise $9$ to the power of $3$ .

$729 + 3 \cdot 9^{2} (- 4 \sqrt{5}) + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Raise $9$ to the power of $2$ .

$729 + 3 \cdot 81 (- 4 \sqrt{5}) + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Multiply $3$ by $81$ .

$729 + 243 (- 4 \sqrt{5}) + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Multiply $- 4$ by $243$ .

$729 - 972 \sqrt{5} + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Multiply $3$ by $9$ .

$729 - 972 \sqrt{5} + 27 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Apply the product rule to $- 4 \sqrt{5}$ .

$729 - 972 \sqrt{5} + 27 ({(- 4)}^{2} {\sqrt{5}}^{2}) + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Raise $- 4$ to the power of $2$ .

$729 - 972 \sqrt{5} + 27 (16 {\sqrt{5}}^{2}) + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Rewrite ${\sqrt{5}}^{2}$ as $5$ .

Use $\sqrt[n]{a^{x}} = a^{\frac{x}{n}}$ to rewrite $\sqrt{5}$ as $5^{\frac{1}{2}}$ .

$729 - 972 \sqrt{5} + 27 (16 {(5^{\frac{1}{2}})}^{2}) + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Apply the power rule and multiply exponents, ${(a^{m})}^{n} = a^{m n}$ .

$729 - 972 \sqrt{5} + 27 (16 \cdot 5^{\frac{1}{2} \cdot 2}) + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Combine $\frac{1}{2}$ and $2$ .

$729 - 972 \sqrt{5} + 27 (16 \cdot 5^{\frac{2}{2}}) + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Cancel the common factor of $2$ .

Cancel the common factor.

$729 - 972 \sqrt{5} + 27 (16 \cdot 5^{\frac{2}{2}}) + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Rewrite the expression.

$729 - 972 \sqrt{5} + 27 (16 \cdot 5^{1}) + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Evaluate the exponent.

$729 - 972 \sqrt{5} + 27 (16 \cdot 5) + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Multiply $27 (16 \cdot 5)$ .

Multiply $16$ by $5$ .

$729 - 972 \sqrt{5} + 27 \cdot 80 + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Multiply $27$ by $80$ .

$729 - 972 \sqrt{5} + 2160 + {(- 4 \sqrt{5})}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Apply the product rule to $- 4 \sqrt{5}$ .

$729 - 972 \sqrt{5} + 2160 + {(- 4)}^{3} {\sqrt{5}}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Raise $- 4$ to the power of $3$ .

$729 - 972 \sqrt{5} + 2160 - 64 {\sqrt{5}}^{3} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Rewrite ${\sqrt{5}}^{3}$ as $\sqrt{5^{3}}$ .

$729 - 972 \sqrt{5} + 2160 - 64 \sqrt{5^{3}} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Raise $5$ to the power of $3$ .

$729 - 972 \sqrt{5} + 2160 - 64 \sqrt{125} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Rewrite $125$ as $5^{2} \cdot 5$ .

Factor $25$ out of $125$ .

$729 - 972 \sqrt{5} + 2160 - 64 \sqrt{25 (5)} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Rewrite $25$ as $5^{2}$ .

$729 - 972 \sqrt{5} + 2160 - 64 \sqrt{5^{2} \cdot 5} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Pull terms out from under the radical.

$729 - 972 \sqrt{5} + 2160 - 64 (5 \sqrt{5}) + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Multiply $5$ by $- 64$ .

$729 - 972 \sqrt{5} + 2160 - 320 \sqrt{5} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Add $729$ and $2160$ .

$2889 - 972 \sqrt{5} - 320 \sqrt{5} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Subtract $320 \sqrt{5}$ from $- 972 \sqrt{5}$ .

$2889 - 1292 \sqrt{5} + 1 \div {(9 - 4 \sqrt{5})}^{3}$

Rewrite the division as a fraction.

$2889 - 1292 \sqrt{5} + \frac{1}{{(9 - 4 \sqrt{5})}^{3}}$

Use the Binomial Theorem.

$2889 - 1292 \sqrt{5} + \frac{1}{9^{3} + 3 \cdot 9^{2} (- 4 \sqrt{5}) + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3}}$

Simplify each term.

Raise $9$ to the power of $3$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 + 3 \cdot 9^{2} (- 4 \sqrt{5}) + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3}}$

Raise $9$ to the power of $2$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 + 3 \cdot 81 (- 4 \sqrt{5}) + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3}}$

Multiply $3$ by $81$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 + 243 (- 4 \sqrt{5}) + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3}}$

Multiply $- 4$ by $243$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 3 \cdot 9 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3}}$

Multiply $3$ by $9$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 {(- 4 \sqrt{5})}^{2} + {(- 4 \sqrt{5})}^{3}}$

Apply the product rule to $- 4 \sqrt{5}$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 ({(- 4)}^{2} {\sqrt{5}}^{2}) + {(- 4 \sqrt{5})}^{3}}$

Raise $- 4$ to the power of $2$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 (16 {\sqrt{5}}^{2}) + {(- 4 \sqrt{5})}^{3}}$

Rewrite ${\sqrt{5}}^{2}$ as $5$ .

Use $\sqrt[n]{a^{x}} = a^{\frac{x}{n}}$ to rewrite $\sqrt{5}$ as $5^{\frac{1}{2}}$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 (16 {(5^{\frac{1}{2}})}^{2}) + {(- 4 \sqrt{5})}^{3}}$

Apply the power rule and multiply exponents, ${(a^{m})}^{n} = a^{m n}$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 (16 \cdot 5^{\frac{1}{2} \cdot 2}) + {(- 4 \sqrt{5})}^{3}}$

Combine $\frac{1}{2}$ and $2$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 (16 \cdot 5^{\frac{2}{2}}) + {(- 4 \sqrt{5})}^{3}}$

Cancel the common factor of $2$ .

Cancel the common factor.

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 (16 \cdot 5^{\frac{2}{2}}) + {(- 4 \sqrt{5})}^{3}}$

Rewrite the expression.

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 (16 \cdot 5^{1}) + {(- 4 \sqrt{5})}^{3}}$

Evaluate the exponent.

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 (16 \cdot 5) + {(- 4 \sqrt{5})}^{3}}$

Multiply $27 (16 \cdot 5)$ .

Multiply $16$ by $5$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 27 \cdot 80 + {(- 4 \sqrt{5})}^{3}}$

Multiply $27$ by $80$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 2160 + {(- 4 \sqrt{5})}^{3}}$

Apply the product rule to $- 4 \sqrt{5}$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 2160 + {(- 4)}^{3} {\sqrt{5}}^{3}}$

Raise $- 4$ to the power of $3$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 2160 - 64 {\sqrt{5}}^{3}}$

Rewrite ${\sqrt{5}}^{3}$ as $\sqrt{5^{3}}$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 2160 - 64 \sqrt{5^{3}}}$

Raise $5$ to the power of $3$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 2160 - 64 \sqrt{125}}$

Rewrite $125$ as $5^{2} \cdot 5$ .

Factor $25$ out of $125$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 2160 - 64 \sqrt{25 (5)}}$

Rewrite $25$ as $5^{2}$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 2160 - 64 \sqrt{5^{2} \cdot 5}}$

Pull terms out from under the radical.

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 2160 - 64 (5 \sqrt{5})}$

Multiply $5$ by $- 64$ .

$2889 - 1292 \sqrt{5} + \frac{1}{729 - 972 \sqrt{5} + 2160 - 320 \sqrt{5}}$

Add $729$ and $2160$ .

$2889 - 1292 \sqrt{5} + \frac{1}{2889 - 972 \sqrt{5} - 320 \sqrt{5}}$

Subtract $320 \sqrt{5}$ from $- 972 \sqrt{5}$ .

$2889 - 1292 \sqrt{5} + \frac{1}{2889 - 1292 \sqrt{5}}$

Multiply $\frac{1}{2889 - 1292 \sqrt{5}}$ by $\frac{2889 + 1292 \sqrt{5}}{2889 + 1292 \sqrt{5}}$ .

$2889 - 1292 \sqrt{5} + \frac{1}{2889 - 1292 \sqrt{5}} \cdot \frac{2889 + 1292 \sqrt{5}}{2889 + 1292 \sqrt{5}}$

Multiply $\frac{1}{2889 - 1292 \sqrt{5}}$ by $\frac{2889 + 1292 \sqrt{5}}{2889 + 1292 \sqrt{5}}$ .

$2889 - 1292 \sqrt{5} + \frac{2889 + 1292 \sqrt{5}}{(2889 - 1292 \sqrt{5}) (2889 + 1292 \sqrt{5})}$

Expand the denominator using the FOIL method.

$2889 - 1292 \sqrt{5} + \frac{2889 + 1292 \sqrt{5}}{8346321 + 3732588 \sqrt{5} - 3732588 \sqrt{5} - 1669264 {\sqrt{5}}^{2}}$

Simplify.

$2889 - 1292 \sqrt{5} + \frac{2889 + 1292 \sqrt{5}}{1}$

Divide $2889 + 1292 \sqrt{5}$ by $1$ .

$2889 - 1292 \sqrt{5} + 2889 + 1292 \sqrt{5}$

Step 2

Simplify by adding terms.

Add $2889$ and $2889$ .

$5778 - 1292 \sqrt{5} + 1292 \sqrt{5}$

Add $- 1292 \sqrt{5}$ and $1292 \sqrt{5}$ .

$5778 + 0$

Add $5778$ and $0$ .

$5778$

Evaluate (9-4 square root of 5)^3+1÷((9-4 square root of 5)^3)

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